Hulu Plus, which launched as an invitation-only service in June, lets people watch current and back episodes from more than 45 shows from ABC, NBC and Fox, including "Modern Family," "Glee," and "30 Rock." Hulu Plus episodes, like the more limited selection available from the free Hulu website, are interrupted by short commercials.

The for-pay Hulu service will be available later this fall on all three of Roku's Internet video players. The devices, which start at $60, connect to a home network using Wi-Fi or an ethernet cable. Roku says it expects to have sold 1 million set-top boxes by the end of the year.

Hulu Plus will also be available to TiVo Premiere DVR subscribers in the coming months. TiVo customers pay an extra $12.95-a-month fee for updated TV listings and services or $399 for a lifetime subscription. Hulu Plus will only be available to buyers of the Premiere DVR for $299 or Premiere XL for $499. The company said it had 2.4 million subscribers at the end of July, down from 3.1 million a year earlier, but it did not disclose how many were users of Premiere models.

The subscription version of Hulu was developed in part to boost profits for its media company parents: News Corp., General Electric Co.'s NBC Universal, The Walt Disney Co. and Providence Equity Partners. The free version of Hulu generated more than $100 million in 2009 from advertising revenue, and it expected to post a third consecutive profitable quarter for the April through June period.